Hi Sudhindra,
Just to give you a start I will tell few points. The program type assignment in budget profile (OPS9) is controlling it. You will find project profile assignment with investment profile in IM configuration. In project master data (CJ20N) also you will get this assignment for WBS elements.
For more details on planned cost flow from IM to PS (IM34) then budget approval,distribution to investment measures (IM52) etc. , you have to search in the forum and read sap help on it. Then only you will understand it thoroughly.
These are just a few pointers to you to understand the process.
Regards
Saurabh